Is there a way for me to have my phone on silent, not have a text message ringtone and still have it vibrate?

The reason I ask is because I am in and out of my college library and classes constantly and having my tone go off in one is no good. But when i switch it to silent, everything automatically goes to rumble, which is good. But there is the ever-looming caution that my silent slider will switch to "not silent" in my pocket.

I can turn off the ringer for the phone and still have it rumble, but I can't turn off the sound for a ring tone and still have that rumble.

Anyways, is there some string editing I can do to alleviate my situation?